Answer:
the person doesnt know its them
Explanation:
Answer:
The first and best defense against plant diseases is a healthy plant, which is the main task of an accomplished gardener. Preventing and managing plant disease begins even before planting, with site preparation and plant selection.
When a plant does not look normal, or as expected, a gardener may assume that the plant is diseased and control measures are needed. To properly diagnose plant problems, the gardener needs to have background knowledge about the plant, the current environment, and the typical diseases or other problems to which the plant is susceptible. Such information can help prevent an inaccurate diagnosis that may lead to unnecessary pesticide use, wasted time and expense, and continued plant decline.
This publication provides gardeners with information on how to establish and maintain healthy plants, and describes a systematic approach to identifying and solving problems that do occur.
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Explanation:
Answer:
a. QRS
Explanation:
In Human anatomy, cardiac cycle can be defined as a complete heartbeat of the human heart which comprises of sequential alternating contraction and relaxation of the atria and ventricles, therefore causing blood to flow unidirectionally (one direction) throughout the human body.
Generally, the cardiac cycle occurs in two (2) stages;
Diastole : in this stage, the ventricles is relaxed and would be filled with blood.
Systole: at this stage, the muscles contracts and thus, allow blood to be pushed through the atria.
The right atrioventricular valve (AV) comprises of three (3) leaflets (flaps) which opens and closes in order to allow for the flow of blood from the right atrium of the human heart to the right ventricle. Also, the right atrioventricular valve is saddled with the responsibility of preventing blood from flowing backward in the mammalian heart.
The QRS complex represents the time necessary for the impulse to travel through the bundle of His, the bundle branches, and the Purkinje fibers to complete ventricular activation or contraction, known as ventricular depolarization. QRS is simply a combination of the Q-wave, R-wave and the S-wave which represents electrical impulses.
